Communication and posting system



Oct. 9, 1945. H. F. MAY ET Al. 2,386,743

COMMUNICATION AND POSTING SYSTEM TELEPTR lo REPERF.

IN V EN TORS H. F MAY J. C. MARSHALL ATTORNEY Oct. 9, 1945. H; F, MAY ETAL 2,386,743

COMMUNICATION AND POSTING SYSTEM Filed Jan. l5, 1944,' l1 Sheets--Sheet2 -HOTRE-:sS-sms O I0 Il l2 I3 |4l5 I6 I7 I8 uNlTs 4H, MA J.C.MA SHALL NBY E ATTORNEY TO FIG. 3

Oct. 9, 1945. H. F. MAY ETAL 2,386,743

COMMUNICATION AND POSTING SYSTEM Filed Jan. l5, 1944 ll Shee-tS-Sheel. 3

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IN VEN TORS HSF. MAY J. C. MARSHALL ATTORNEY FIG. 3

oct. 9, 194s; H. F. MAY ETAL 2,386,743

COMMUNICATION AND POSTING SYSTEM Filed Jan. l5, 1944 ll Sheets-Sheet 4NP (UNITS) coDE TO FIG. 5

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Oct. 9, 1945. H. F. MAY ETAL COMMUNICATION ND POSTING SYSTEM Filed Jan.l5, 1944 1l Sheets-Sheet 5 mom .vom

INVENTORS H. F. MAY

J, c. MARSHALL ATTOLNEY Oct. 9, 1945. H. F; MAY I-:TAL A l 2,386,743

' COMMUNICATION ,IND POSTING SYSTEM I o T FIG. 9 (D u) (D DATA (UNITS)INTERMEDIATE Rows oI TO Ia n I 2 ND DIGIT IDENTIFICATION IST DIGITIDENTIFICATION To F'G' 3`- INvEN'roRS 0 I-I. EMAY J.c.MARsI-IAI L L9' BY/Ln/.aM-z

ll. ATTORNEY Oct'. 9, 1945. H. F. MAY ETAL COMMUNICATION AND POSTINGSYSTEM 1l Sheets-Sheet 7 Filed Jan. l5, 1944 ATTO R N EY Oct. 9, 1945.||z F. MAY ETAL 2,386,743

COMMUNICATION AND POSTING SYSTEM Filed Jan...15, 1944 11 sheets-sheet 8lATTQRNEY Oct. 9, 1945.v

H. F. MAYv EI'AL COMMUNICATION AND POSTING SYSTEM Filed Jan. 15, 1944FIGA. 9

1l Sheets-Sheet 9 INTERMEDIATE o9"653 0952553 095653 `HMH HHH AHHH 9' E-F- G- H h. 0 TIME (TENs) T|ME(uN|Ts) 2 ALT. (TENS) ALT. (uNlTs) l 9 com:TRANS. 22 '3 come` TRANS. '7 con- TRANS. i 2' cons TRANs. 2' lo v T, 145, le 4, 22 5, l n L s 'lJ I9 1, 23 7, I l2 le 2o 24 m4 F1612 nal r|s.2Flcla Plas I F'G' 9 lNvENToRs H. F MAY F'G' "6'7 J.c. MARSHALL no loNo.5 Fles ATTORNEY To FIG. a

Oct. 9, 1945. H. F. MAY Erm.' I 2,385,743

COMMUNICATION AND POSTING SYSTEM Filed Jan. 15,"`1944 11 sheets-sheet 1o'TO FIG. 7

GROUP 3 .GROU 2 GROUP H. l-MAYV FIG. BY J. C. MARSHALL www ATTORN EY 11Sheets-Sheet 11 FIG. I3

H. F. MAY ErAL Filed Jan. 15, 1944l LOCAL KEYBOARD COMMUNICATION ANDPOSTING SYSTEM Oct. 9,` 1945.

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Patented Oct. 9, 1945 COMMUNICATION AND SYSTEM.

Harold 1i.Y May', Valley Stream, and; Joseph! Marshallg. Baldwin, N. Y.,assg'nors to The Tele.-

rcsister- Corporation ration of Delaware Appiication January 15, 1944;SerialNo. 518,37()

(el. rtlz-3535 This invention relates generally to communication andposting systems for displaying information or data in regard to anumberof' different items by means of groups. or rows of indi'- cators whichare automatically and selectively actuatable or settable in response toincoming signals to display information or current changes provementover the communications and postingv system disclosed in the patent toJ. C. Marshall and M. L. Haselton, No. 2,246,449, issued' June 17, 1941.

In systems for recording and. posting4 flight plans and night progressreports of aircraft and other messages relative to the control ofaircraft, hereinafter referred to as trallic oo ntrol systems, theinformation thus posted on, the bulletin ,or announcing board usuallyrelates to numerous nights, and the items posted usually are arranged ingroups according to thavarious marker or Fix classifications, asexplained in the aforesaid Marshall et al. patent., and preferably arearranged within yeach group in accordance with the expected or estimatedtime yof passage, or arrival of the, aircraft at the various recordingor marker. points en route and at the airport. The nightdata yposted mayhave to. be changed from time toA time during the progress of the ightsas the result of conditions affecting the progress of aircraft, such aspoor visibility, ice, changes in the direction and velocity ofthe Wind,the necessity for blind landings, andY other emergency conditions.

The information posted may comprise numerous data, such as the nightdesignation symbols followed by a section number, if any; information asto the direction of the various flights; the airway traic controllersestimated time when the aircraft Will pass over or land at, certainmarker points on the flight route; the timethe aircraft actually passesover or lands. at each marker point; the expected approach time when thepilot may receive instructions to start his;

f An additional. object is animproyodarranseapproach to @landing field;proposed altitudes at wliilcba clearance has been issued to cross cachmarker or flight path; the altitude, at which the aircraft actuallycrosses the various markers ,f and the. landins sequence number'assigned' totalidinss under instrument conditions. In addition to the,foregoing. other information may bc posted outheiiieht progress displayboards. Such for example. as an indication that a clearance through amarker or fix has. been issued; ariiildication of a flight over theairport; an indication of a stop en route, the expected approach time,-or that if; a delay is encountered tbc dcercc Yof such delay is unknown;and an indication that an. aircraftnas been cleared tothecirbcrt controltoweror range station sothattherc will be n0 delay in landing. n

Local communication. facilities comprising known tolcphorie'or telegraphwire or radio equipment be omnioyedto establish. communication .between`the air line companysdispatch of,- ces and the various aircraft,airport control towers, the. localcommunications operator oi 4the airwaytraic cor trol, government ,regulating b11- reaus.y lio cal militaryOperations oiioes if' any., and other airports. Que of the objects ofthe, invention is animproved System. andecuipment for automaticallyreceiyings.- recording and b ostinstlie desired data in resardto venousitems. particularly aircraft' or other yehioles, which Veouiplii ont is,responsive to incoming Signals, for automatically recording and costingcurrent orchangcdinformation in regard.' .tothe Various aircraft orothoritcms.

Another obioct is avpostnsor announcing, systemi andparticuatly aSystem. adapted ,for flight control.. which. utilizes Ytwo Aboardsbaring indicators carrying substantiallytbo information. or on whichcertain ,information is duplicated, .one of which boards arccord boardin which .the flights or otheritems may be recordedand posted vrandomorderand the other an anf noiincins or display .board in whichthe-various flights or other vitems may be displayedand maintained inany-desired sorial .crd'er or Scduenoe. f l i i Still another Objectisthe, provision of means operable at. will for automaticallyrewriting theinformation on the display board accordance with the data stored ontherecord boardginwhi'ch a multiplicity of rows ofY indicatinsdcvices inthc` Adisplay board may simultaneously or concurrently berewiitten by amultiple. rovyseqlldllng operationment whereby the order in which theitems are displayed on the display board may readily be changed at willin accordance with a predetermined chronological sequence.

Another object is a system in which the positions of the items displayedon the display board respectively are determined by the settings of newposition posting units associated with each row of indicators in therecord board.

A further object is improved flight or item 1ocator apparatus in whichall flight or item identification storage devices are comparedsimultaneously with the identification data' of signals incoming to thelocator apparatus. i

Still another object is a system of the character described in which theinformation recorded in the record board may automatically betransferred to the display board without affecting or changing thesettings of the recording devices in the record board, whereby therecord board provides a convenient means for checking the accuracy ofthe information displayed at any time by the display board.

An additional object is means for recording the present location of thenights or other items posted on the display board and recording meansconcurrently operative for preselecting the new positions to which theinformation on the display board may subsequently be transferred.

Still another object `is means for taking the information stored in therecord board in a sequence determined by the new position recordingdevices and temporarily storing the same, and subsequently resetting amultiplicity of rows of indicationg devices concurrently orsimultaneously in the display board, to minimize interference with thedisplayed record.

Various other objects, advantages and improvements will be apparent fromthe following de- Ytailed description of one illustrative embodiment ofthe invention, taken in connection with the accompanying drawings, inwhich:

. Fig. 1 is a view, in diagrammatic form, of certain transmitting andreceiving apparatus including seeker mechanism suitable for use with thesystem of the invention;

Fig. 2 shows a local-keyset in diagrammatic form adapted for use withthe system;

Fig. 3 showsvarious selecting, distributing and indicator pulsingapparatus, togetherv with new position recording indicators associatedwith rows lll to I 4 of indicators of the record board;

Fig. 4 is a view of other distributor apparatus, together with newposition recording indicators associated with row of indicators in therecord board, andnew position code translating relays andsequencecollection switching apparatus;

Fig. 5 represents diagrammatically, a plurality of rows-00 to I 4 ofindicators in the display board;

Fig. 6 shows flight identification and data storage relays and presentposition recording relays, togetherrwith indicators for recording theFix and flight number information in rows 0I to I4 in the record board;Y

Fig. 7 shows flight identification code translating relay apparatus andcertain selection and sequence apparatus employed;

Fig. 8 illustrates a distributor andassociated relays employed forsequencing the items posted on the display board;

. Fig. 9 shows diagrammatically various data recording indicatorsemployed in the record board,

together with associated code translating relays; Fig. 10 shows variousstorage relays employed in connection with the sequencing operations;

CTI

illustrated herein, data in regard to the movements of a, number ofaircraft within a given area of a terminal or other flight control zoneare recorded, and preferably are visually posted, on a record board,shown in the upper right hand portion of Fig. 13, and are displayed inpredetermined sequence on the display board shown in the lower righthand portion of the figure. Rotatable indicators, which are arranged inhorizontal rows,

or tiers designated 00 to I4 preferably are employed as the recordingand display devices. Each row of indicators is identified with a certainflight and is adapted to display the fiight identification number andflight information or data, for example, the time at which the aircraftpasses or reaches a particular location or marker point, referred to inthe art as a Fix, and the altitude of the aircraft at the various Fixpoints, and also any additional information which it may be desired torecord or post on the record and display boards.

While the iiights may be recorded or stored in the record board inrandom order, it is highly desirable that in the flight progress displayboard the flights and information in regard thereto may be displayed ina desired chronological sequence, the indicators also being arranged ingroups corresponding to the different Fix points to which they relate,such as Fix l, Fix 2 and Fig. 3. Both the record board and the flightprogress display board may be located at an air trafc control center,such as an airport, where the fiights terminate or traverse apredetermined area associated with or controlled by the airport, and areposted on the display board Vby means of indicators so as to be visibleat all times to the airway traffic personnel or others interested in theprogress of the nights thus posted.

At the traffic control center a local keyboard and mechanism associatedtherewith is provided for initially setting up on the record board, andif desired, on the display board, information such `as the flightdesignations, and the estimated time ,and altitude and other data inregard to the various aircraft at the several fixes or marker points,the keyboard also serving to initiate multiple row sequencing of thedisplay board to enable rearrangement of the order or sequence in whichthe flights are displayed.

The signals incoming from the various places for posting the recordboard and the display l board may be of any suitable type. Usually, andin accordance with conventional telegraph practice, permutation codesignals, for example, fiveunit code signals, are employed, which signalsmay be initiated either at the station IDI, Fig. 1, and transmitted bywire or line LI to the receiving equipment, or the signals may betransmitted by radio transmitting apparatus, such as teleprinterssituated in the aircraft, while the aircraft is in flight and thustransmit signals which are received by radio apparatus, Fig. 1, situatedat any suitable location. Such radio receiving apparatus may compriseaudio frequency filters,

vents A2.231.215 and 2,252,232.

:each associated with aan aircraft and tuned to the frequency 4of 1 the:audio frequency generator of the-.associated:aircraftfeachfof the'ltercircuits 'beingi connected by ta, conductor 'suchas L2 'or'. L3y todistributorsA i105 and |06; for causing'the received. messages tobestored by reperforato-rs :Marshall-etal.-.Patent-1No. l2,246,449. -Anyother suitable method f of transmitting fand receiving signals for,contr-ollingfand'. actuating. the recordingtand post-ing apparatusmayfof 1 course, be

employed.

Posting the recordfboard and the 'display board by incoming lsignals Themanner in which signals received from. one

of 1vthe ltransmitting stations, for example, I from I teleprinter I Iover the line L, Fig. 1, are employed to control the operation of thetime and altitude record board and display board indicators TT, TU, ATand-AU shown in Figs. 5, 9 and 13, and the monitor printer MP, Fig. 1,is generally as described in the Marshall et al. patent except that thecircuit is modified in certain respects in accordance with the instantinvention. Assume, for example, that the record board (Figs. 3, 4, 6, 7,9 and 13) and the display board (Figs. and 13) are located at theWashington Airport, and vthat the operator 4at station I BI, which maybe located at one of the nx points. for example, Philadelphia, which isdesignated as yFix 1, desires to transmit. to the Washington Airportinformation in regard to a flight identied as No.. 34, which is passingover the Philadelphia x at 1:35 p.v rn. at analtitude of 4590 feet. Thisinformation will be received and printed on the multiplex printer MP,Fig. l, and alsoposted on the record board and display board, Fig. 13,at the Washington Airport.

The operator at station-Ilrat Fix l actuates the keys of his-teleprinter keyboard and sends numerical and functional "characterscomprising the message inthe following order: 3 4,1 3 3 5 vspace space 34 124 -and'end-of-message. The

rst twocharacters Sand 4represent the flight identication'number 34,the-thirdcharacter 1 the x selecting number corresponding toyPhiladelphia, the fourth character 3-is the vrange or selecting signalfor the time postingindicators, the fth and sixth characters 3 and 5 arethe -tens and units digits, respectively, of the time, .and the'twospacing signals are interposed between the rst land second part ofthe'message transmitted. The'characters 3 and 4 :followingthesecond'space signal again represent the night identification number.and digit l. the fix number,..2 the rangeor selecting signal for thealtitude posting indicators, characters 4 and 5 the thousandsandhundreds digits ofthe altitude, and the end-of-messagesignal',fusually transmitted by the/key Lfofthe printerf keyboard.

The keyboard yprinter Ill! may be any of the well-known typcssucl'i asshown in the Martin et al. Patent 1,745,633 or in tl'le-NoxonVetal.'Pat- These start-stop printers send and also record thetransmitted signals on a tape, which signals are composed of markingyand spacing'units comprising a start impulse followed by a permutedgroup of ve marking and spacing impulses in various combinationslrepresenting the character transmitted, each group being terminated bya Arest impulse which,r is. off Yopposite line. condition to that ,ofythe start impulse. The-operation of the ightidentica-tion keys causes astart impulse to be -applied to-thedi-ne L, thereby setting the`receiving 5 -distributor Idil-into operation. This impulsey is followedby the code signal for the number 3 -followed-.bya rest-impulse. Theoperation of distributorlil .causesY thecodeunits of the signalvreceived --to -be Vtransmitted overy ve conductors to a reperfora-torIS7, a sixth conductor- 6' ofthe group serving tofoperate ythey punchmagnet of the reperto-raton The reperforator perforates 'the tapelissuing ltherefrom inv accordance with `the-.signalsreceived, -and stepsthe tape ahead into position -forthenext succeeding perfor-'atingoperation corresponding tothe second digit of theflig-ht identificationnumber. Any of-various known types of perforators may be employed, forexample, as disclosed in the patent to Hoover v2,252;.-85/I oreaprinterreperforatory such 4as disclosed in the Dirkesat'faLPatent 2,193,809.Since theipermutation-signal forv the vdigit 3vhas-the code unit tion-lymarking `in character, conductor fI, .has-.marking .potential appliedthereto and thev rremaining conductors-2 to.5 have spacing-ornocurrentcondition applied thereto, thereby caus- Ving a`singleperforation to be made in the-tape l`at this time` correspondingto the numeral-1.

The conductors I to 5 are connected by means 30.0f a, cable IIDIto thewindings of four end-of- -message relays EMI to-.ElVIAY of the-,group B,the conducto-rs Land 2 ofcable IIB being connected to 4th'e left. handand vinner- .operating windings, respectively, of relay-EMI,` andconductors 3,4 and 5 -of ythe cablelare connected to the operatingwindings 4of relays EM2, Y EMB andEM, respectively. .The application ofra marking signal to conductor. Lof the cable. causes relay VEMI to'op-.erate over a circuit fromA ground at itsleft hand 40winding.to markingbattery appliedtothe conductortbythe.distributor H14. Relay EMP-locks...by.meanslcf-itsright handmake contact and armature III to batteryontconductor II2-sup plied-.bythe vbreakcontact of the sixth `pulse re-.laylIALoithedistriloutorA HM. lThe cperationof relay-EMIis-witnout'eiect atth'is time, the ren lay releasingupon the .subsequentoperation' of 'the sixth pulse relay.

45In. asimilar manner vthe signals correspondingr@ the. crease-1,3, 3ands are receivedy and :stored inthe-perforated Atape tI, the relays EM!"to-.Eli/Ilioperat-ing incode combination to read .the character eachtime-a digitor acharacter .signal` islreceived. yThe two: spacingsignals im- .medatelyfollowingthe digit 5 cause the tape to `be.stepped` aheadtwiee in known-manner. Sig- ,.nals correspondingto thedigits '3,4, 1,2, 4 and 5, respectively,` follow the two-Space signals'and areastored inithe tapel tIfand also'cause the op- 60 eration of theend-of-Inessage relays `EMI to tFM4 in code combination corresponding'tceach of .the digits ystored in the tape.

Immediately followingthe signal :for the'digt 5..is theend-of-message-signalhaving the code c5 units`v1 2,and,4 spacing andunits y3 and V5tbereof marking in character. This signal causes relaysEM2 andiEMd to operate and lock to battery onconductorlIZ, YandrelaysEMI and EMS .to ,remain .unoperated vGround at armature-lMfandbreakccni-,act of relay'EMI isextended .toarmature IIEandimakeycontactof operated relay.l .l\[21 armature` I IB- and breakcontact of unoperated` relay EMS, larmature III vand make'c'ontactcf A,operated relayrEM, and th'enceby-con T5 ductor II8 through .the windingof;relay1L to grounded battery, thereby causing relay L to operate andlock over its make contact and armature |20, conductor I 2|, and breakcontact and armature |22 of release relay RS5 to ground. Conductor I2Ialso extends, through a conductor |24, to contacts |25 of a tight-tapeswitch or auto-control AC which, when a complete message is stored inthe tape loop between the reperforator and tape transmitter, are closed,thereby applying ground to the locking circuit of the relay L holdingthe relay operated.

The operation of relay L, at its armature |26 and break contact,interrupts the circuit to terminals 3 and 1 of the bank A of the rotaryseeker switch SS, and at the make contact of its armature |26 relay Lapplies ground to the corresponding armatures |26 and break contacts ofthe relays K, RI and R2, to terminals I, 2, 4, 5, 6 and. 8 of bank A ofthe seeker switch SS. If it be assumed that the switch wipers areresting on their terminals I at this time, ground at terminal I isextended by way of the switch wiper of bank A, break contact andarmature |28 of the seeker stepping magnet SSM, and thence to groundedbattery, thereby causing th'e stepping magnet to operate onself-interruptions and advance the wiper for the bank A thereof to itsterminal 3 which has ground removed therefrom by the operation of relayL.

With the wipers of the banks A, B and C of the switch' SS resting ontheir terminals 3, a circuit is completed from battery at the lowervouter armature |29 and make contact of relay L, conductor 3 of cable|30, to the upper operating winding of transmitter-connecting relay TC,conductor |3I, terminals 8 and 3 of bank C of the seeker switch andwiper thereof, conductor |32, and thence by way of conductor 1 in cable|33. Cable |33 extends to Fig. 4, and conductor 1 thereof is connectedto the winding of a start magnet SMI associated with the rotarydistributor DRI, andthence by way of conductor 4 in cable 40| to thelower break contact and armature 100 of a sequence startrelay SST, Fig.7.

From the armature '|00 th'e circuitl continues by way of conductor I incable 40| and cable |33, Figs. 3 and 4, to the stop segment of thesegmented ring I of rotary distributor DR2, and thence through the brushb to the solid ring 2 of the distributor to ground, thereby operatingthe transmitter-connecting relay TC, Fig. 1, and the start magnet SMI,Fig. 4. Th'e operation of relay TC, Fig. 1, connects the transmittingtongues and the tape step magnet TS of the tape transmitter TTRI, inmultiple with the monitor printer MP, through conductors to 6 of cable|35, and through cable |40 to the five solid rings 2, 4, 6, 8 and I0 ofthe rotary distributor DRI, Fig. 4. Conductor 6 is connected to theevennumbered segments 2, 4, 6, 8, I0 and I2 of the segmented ring I I ofdistributor DRI. Relay TC, Fig. 1, locks from grounded battery throughits lower winding and contacts 1, and conductor I4I to the middle breakcontact 302 and armature 3300i release relay REL, Fig. 3, to ground.

Operation of distributor DRI The start magnet SMI, Fig. 4, havingoperated in series with transmitter-connecting relay |40, and throughconductors I, 1, I3, I!! and 25 of cable 402, Fig. 4, to the groundedwindings of th'e 1st digit identification storage relays III to |15,Fig. 6. Since in the example assumed, the first digit of the flightidentification number is the digit 3, which has one marking and fourspacing pulses, the transmitting tongue I of the tape transmitter 'ITRIis the only tongue in closed position, thereby causing relay III only ofthe 1st digit identification relays to be operated. This relay locksover a circuit from ground at its winding through its make contact andarmature 603, conductor 60|, to the upper break contact and armature 303of relay REL, Fig. 3, to grounded battery. The arrangement of relays andarmatures in the 2nd digit identification storage relay group, and alsoin the x group, is th'e same as that in the 1st digit identiiicationgroup shown, except that there is no blank lead BL in cable 601connected to the armatures of the x relay groups.

The brushes of distributor DRI, as they advance, next contact segment 2of ring II, and the brush b5 completes a circuit from grounded batteryon segment 2 of ring I2, through the brush and segment 2 of ring |I toconductor 5 in cable |48, and thence to the tape stepping magnet TS andthe print magnet PM, Fig. l, thereby printing the character on themonitor printer and also stepping the tape in tape transmitter TIRI. Asthe distributor DRI rotates, the brushes thereof close circuits tosegments 4 of rings I, 3, 5, 1 and 9 connecting the 2nd digitidentification relays, shown in Fig. 6, to the tongues of the tapetrans- .).1 mitte-r TTRI, Fig. l, in a manner similar to that of thepreceding character, thereby actuating the relays in the second digitidentiiication group in accordance with the code for the digit 4.

imilarly, as the tape is advanced, in transmitter TTRI, the remainingcharacters are printed by the monitor printer, and are transmitted bysegments 5, 8, I0 and I2 of rings I, 3, 5, 1 and 9 of DRI and stored inthe Fix relay group, and the Range and Data (Tens) relay groups RI toR5, DTI to DT5, and corresponding relays in the Data (Units) group shownin Fig. 6. When the brush h6 of distributor DRI reaches segment I2 ofring II, this completes a circuit from grounded battery on segment 2 ofring I2, through the brush, segment I2, conductor 6 in cable |40, to thetape step magnet TS of the tape transmitter T'IRI of Fig. l, and at thesame time energizes the print magnet PM in the monitor printer,recording the last received character of the data. Stepping of the tapetransmitter advances the next character under the sensing pins which isspace in this example.

When the brush b5 of distributor DRI reaches segment I4 of segmentedring I, ground is applied from segment 4 of ring I 2 through the brush,segment I4, conductor 9 in cables 40! and |33, and conductor 9 out ofcable |33, Fig. 3, to the start magnet SM2 of distributor DR2, andthence to grounded battery, actuating the'start magnet and releasing thebrush b of the distributor for rotation. As the distributor DR2 leavesits rest position, the circuit through segment of ring I is opened,thereby deenergizing start magnet SMI of distributor DRI, Fig. 4.Distributor DRI then comes to rest with its brushes on its stop segmentI. Distributor DRI waits until distributor DR2 has completed its cycleof transmission hereinafter described, before continuing to take theremainder of the message from tape transmitter T'I'RI.

through cable 606 to the contact bankofthelll` Selection of gang relaysinthe-record board" Each horizontal row of the record board Icontainsstorage orrecording units NPT, NP U, `F, IT, IU,` TT, TU, AT, AU,the upper row I4 of which is shown in V,Figs. 3, 6 and 9.' Preferably, Qalthough not necessarily, these-are recording inf.v dicators Yof vthetype disclosed inV Haselton et al..v Patent No. 2,155,825, issuedApril., 25, 1939- SuCh indicators are providedv with' a set of equallyspacedl contacts corresponding in number Vto the.

number of positions to which the indicator drums may be moved, thecontactsbeingj arranged in.

continuousseries. The wiper arm is attached to the indicator drumassembly and engagesthe contacts of theindicator in accordance withtheinstant setting of the drum; vvfor example, if the drum is set todisplay the digit 1, the wiper will be in engagement with contact I;similarly,

if the indicator is set to its blank position, the 1 associated.wiperwill be in engagement :with-its blank contact BL. The wiper contactassemblies herenreferred to are illustrated schematically inarccuateform in the drawings to show more cle'arly theelectrical circuitsconnected thereto. It ,will be understood, however, that these wiperstake settings in accordance with the ight identi,-

cation and information digits or symbols posted by the indicators. Aseach ,ofthe indicators reaches its blank' orhome position, during theAtransmission to the indicator of restoration pulses in a mannerhereinafter described, the restora-v tion Vcircuit to ground is openedandanactuation or resetting circuit is closed, by a switch element,

such as s in the indicators of;Fig., 9, thereby to cause the indicatorto stop when it reaches its homeposition and its coil switched to anactuation circuit, as disclosed-in the Apatents to Haselton 2,G49,l99,issued Auguste, k1936, vand Hicks et a1-.'2;i89,581, issued February6,1940; The subsequent application of the resetting or actuationimpulses tothe indicator causes the switch members to be restored to itsformer position whenv the indicator leavesits blank position vduring theresetting operation; Fifteerr of such rows of 'in= dicators areindicated in the drawings, ,the 'bottomrow being shownV in-the upperportionsA of Figs. e and 7 yand the lower 'portion o'f- Fig; 9; and theintermediate rows 0I -to-IZVbeing'in-di'-- cated diagrammatically-inFigs. 3, 6-y and 9;v It will be understood that in practice a-great'manyl. more rows than those indicated will be employed in the recordboard;in anY average size instalrlation-v there may be approximately 2500 rowsof such indicators. The indicators F, v-IT and-IU in each row, Figs. 6and '7, have initially been set-.

in a manner disclosed hereinafter-to positions corresponding-tc theflight number to be recorded I in that row; the settings of these'indicatorsfde-` termine whether or not the information stored 'inl theFix and Identification relay storage-groupsshown in-Fig. 6fwill operatethe gang'relay associated with that 4row-inthe recordboard,- such asrelay GAI yof Fig. 3S As'soon as the Fix and-J Identiiicationdigits havebeenrecorded,- selection circuits are -set-upin thepyramidal-ar-rangement of contacts on the"storage-relaysl as shown I forthe -1st digit' Identification,- Fig.- 6.1A These4circuits-are-multipledyto the corresponding indicator units-in each ofthe rows of the record "70` digit Identification storage relaysaremultipled through a cable v6115 to the bank of-co`ntacts-ovv board;for example, the circuits from theclst the ITindicators in each of thehorizontal rows ii to Ill.v Similarly, the. circuits jfrom the 2nd.

digit Identification-storage groupare multipled III applied thereto, andin those rows where the.-

IT indicator is resting on terminal 3, as Figq, a circuit will becompleted to operate the associated ITC relay in that row. Let us assumethat row It hasbeen assigned to flight 34,.Fix.1.

In other rows where the IT indicator also is resting on terminal 3, theITC relay will also operate, but sincethe selection of a given rowdepends' upon -an exact match inzall three indicator positions IT, IUand. F, a complete circuit can .only be established in the row assignedto that ilight. Continuingv with our example, the 2nd digit identicationstorage relays of Fig. 6 will apply ground .to conductor S in cable 666,and since the wiper,

of the indicator IUI in row I4 is resting on terminal 4, the -relay IUCIll will operate. the Fix storage relays .will energizegleadl ,in cable601 and since the wiper of the F indicator in rowV I4 is resting on thisposition, theFCIli relay will be operated. The. combination of operatedrelays ITCIA, IUCMfandFCII 'completes a series circuit from groundthrough make :contact and armature 6 I 0 .rof relay IUC I It,A make lcontact and armature GII of relay ITCIII, conductorl?, makezcontact-and.armature A6I3 of relayFCI'4, conductor III, winding of gang relay GAM,Fig. 3, to grounded battery, operating Arelay GAIA.

The relay GAIlIis maintained energized throughY `the circuitpreviously..described, so long as the permutation relays, inA the 1stfdigit'Ident; 2nd

digit Ident, and Fix storage groups remain oper- Y ated,A and-theselatterrelays are held operated until the brush b. of distributorDRE has reached segment 45 .ofthe distributor ring I, and therelease-relay lREL has operated to remove battery, at 'its armature`andl break` contact 3Il3,rfrom the holding circuit 60 If for the storagerelays of Fig.Y 6.

Theoperation oirelay GAIA connects by means of-cable y338,-=the coilsoitherecording indicator units NPT; NPU; F, IT, IU, TT, TU, AT-and AU oflrow I- through the pulsingcable 3Il5vto lthe groups of range relaysNP,F, L T, A, and also to the group-of. pulsingrelays PI, P2, P4 and Pl andAGrofv Fig. 3; also connects ground `at 336 over conductors 4 to II incable 338 tocontacts .onthe present position PPT and PPU. relays of row,I4, Fig. 6. The

purposeofltheseirelays is to control the selectionv of the particularArow .of indicatorsin` the display boardwherelight-34, Fix 1,. isatpresentdisplayed.- .Thepresent positiontens PPT and unitsA PPU1relays",` eight in number, vare ofthe mechan.` ical-iatching,electrical-reset. type, and store in four Aunit permutation code atwo-fdigit `number correspondingfto the-1`owy number in the displayboard where flight 34,-Fix 1, is posted.

Fig. 12 shows the-details of oneform= of. me-

chanical-latching type-of relay, which, may be employed.Y Theoperatingwinding lloi Athe `relay is connected, in` multiplewiththe.other.relayA windings o, througha conductor Bel -toa source ofgrounded -batterytk- All the reset Iwindings R are connectedinseries-bymeans ofaconduc-` tor 65o; to the source of battery When the Similarly,

The operation of relay GAIII operating winding o fv any of the relays isenergized, it attracts its armature a and closes a circuit through itsmake contact, for example, from conductor 4 in cable 333 toA conductor Iin cable GIG. As the armature a moves towards its make contact, it liftsa pivotally-,mounted mechanical latch b which drops down behind thearmature a and keeps it locked in circuit-closing position until therelease or reset winding R is energized. Energization of the resetwinding attracts its armature and raises the latch b, whereby thearmature a returns to its open position, either under the iniiuence of aspring or by gravity.

The ground circuit from 335, Fig. 3, is applied selectively through theclosed contacts of those relays PPT, Fig. 6, which are operated, andthrough certain of the conductors I, 2, 3 and 4 of cable BIE to thewindings of relays PTI, PT2, PTS and PT4, Fig. 7. Similarly, thecontacts of those relays PPU which are operated, extend ground overcertain of the conductors 5, 6, 'I and 8, cable SIG, to the windings ofrelays PUI, PU2, PU3, PU4, Fig. 7. The relays PU and PT operate incombination in accordance with the permutation codes stored on relaysPPU and PPT and serve to select one of ten cable leads 0 to 9 throughthe conventional pyramidal arrangement of armatures and contactsassociated with the relays PU and PT.

Let it be assumed that flight 34, Fix l., appears in the bottom row 00of the display board shown in Fig. 5. Consequently, the permutationcodes for 00 will be recorded on the present position storage relays PPT.and PPU of row I4, Fig. 6, of the record board. This combination ofcircuits will have operated relays PTI, PT2,PT4, PUI, PU2 and PU4, Fig.7, so that the 0 lead in each pyramid of these relays will have groundapplied thereto from the apex 'H6 or 'II'l. Ground will be fed from apexII'I through the operated inner armatures and make contacts of relaysPTI, PT2 and PT4 and the unoperated inner armature and break contact ofrelayPTrS, through conductor 0 to operate relay PT00, Fig. 7, and the 0contact of each of the relays PT00 to PTB will have ground appliedthereto from the apex H6, through the multiple cable H3. Since relay PTBis the only one operated, however, the conductor 00 in cable Il will bethe only one having ground applied thereto. This willcomplete a circuitfromgrounded armature 'IIS of energized relay PUI through operated innerarmature and contact of relay PU2, non-operated inner armature and breakcontact of relay PU3,

operated inner armature andmake contact of re- Y lay PU4, lead 0 ofcable 1I8, contact 103 of relay PT00, lead G0 of cable 10|, to thewinding of display board gang relay DGA00, Fig. 5, to grounded battery.The operation of relay DGA00 connects the coils of the display boardindicators IT, IU, TT, TU, AT and AU to the pulsing multiple throughcable 50| and cable 305, Figs. 3 and 4, to the range or selection relaysNP, F, I, T, A, Fig. 3, and the pulsing relays PI, P2, P4, P1 and AG.The display board indicators need not be of the recording kind employedin the record board, and may be of any suitable display type such asdisclosed in the aforesaid Patents Nos.

2,049,499 and 2,189,581. The switch members s on the indicators open therestoration circuits to ground when theindicator drums reach their blankpositions, the switch members being re-v closed when the indicators arestepped from their blank positions during the resetting operations.

During the operation of distributor DRI a comdescribed later.

bnation of range storage relays RI to R5, Fig. 6, has been operated toapply ground either to lead I or lead 2 of cable 620. In the examplecited the range selected (time) was No. 3, the permutation code forwhich energized relay RI only, and consequentlyv ground was appliedthrough the contacts of relays RI to R5, lead 2 of cable 620, to theWinding of relay T, Fig. 3, and thence to grounded battery. Relay Toperated and at its armatures and make contacts connected through thecircuits from pulsing relays PI, P2, P4 and P'I to pulsing leads I4 andI5 in cable 305, which are extended, through contacts of relay GAI4 andcable 338, to the windings of the time indicator units TT and TU, Fig.9, of row I4 in the record board, and are also extended throughconductors 3 and 4 in cable 50| and contacts of relay DGA00 toindicators TT and TU of row 00 in the display board, Fig. 5.

Operation of distributor DR2 for pulsing the selected indicators In Fig.5 a relay M is arranged to tie together the pulsing multiples of thevarious rows in the display board. As later described under Sequencing,.it is necessary to utilize five separate pulsing multiples 50| to 505in the display board. However, for the purpose of posting a singleflight, these multiples must be tied to the range and pulsing relays NPto AG shown in Fig. 3. When relay M is operated, as described below, thecorresponding leads of the pulsing multiples 50|, 502, 503, 504, 505 aretied together by means of the multiple connections m on the contacts ofrelay M. The first operation accomplished by distributor DR2, Fig. 3, asits brush arm b leaves the rest position is to apply ground from ring 2to segment 2 of ring I, and thence over lead 2 of cables 30| and |33 tothe winding of the M relay, Fig. 5, to grounded battery. Through itsinnermost make contact a locking path for relay M is maintained overlead 3 of cables |33 and 30|, through the break contact and armature 308-to ground on relay REL, Fig. 3. The relay M remains locked up until theREL relay is operated from segment 45 of DR2 at the end of the cycle ofthe distributor. The brush b ofV distributor DR2 next closes a circuitto segment 3 of ring I, but this circuit is utilized only when postingfrom the keyset shown in Fig. 2, which will be The next circuit closedby distributor DR2 is to segment 4 of ring I. It will be noted that theten even numbered segments 4 to 22, inclusive, are connected togetherand furnish an operating path for the pulsing relay PI, Each time thatrelay P1 operates, battery through break contacts and armatures 3 I 0and 3I I ofrelay AG is fed through armatures 3I2 and 3I3 and associatedmake contacts of relay P'I, make contacts and associated armatures 3l4and SI5 of relay T, to leads I4 and I5 in the pulsing multiple 305. Theten pulses generated in passing over segments4 to 22 on ring I ofdistributor DR2 restore the selected indicators in the display board andrecord board to their blank positions, irrespective of what their formerpositions were. As each indicator reaches its blank positiontheerestoration circuit to ground is automatically opened by theindicator switch member s or s', thereby stopping the indicator in 'thisposition. When the brush arm of distributor DR2 reaches segment 24,ground from ring 2 is fed through the brush over conductor 3I8 to thewinding of relay AG, and thence to grounded battery, causing Arelay AGto operate. The operdistributor, thereby storing the Identication, Fix,Range and Data characters of the second portion of the message in thestorage relays shown on Fig. 6.

As the brush bIi of distributor DRI, Fig 4, passed segment I2 of ringII, a circuit was closed from battery on segment 2 of ring I2, throughsegment |2,over conductor 6 in cable |40, to the print magnet PM of themonitor printer and the tape step magnet TS of the tape transmitter.This operation printed the last character (5) of data on the monitorprinter and at the same time advanced the perforated tape to bring theendof-message character under the sensing pins of the tape. transmitter.When this occurred, circuits were closed over leads I, 2, 3, 4, 5 incable |50 to the windings of the RSI to RS4 relays of the group A inFig. 1. The combination of operating paths representing the code for theend-ofmessage signal caused relays 2 and 4 to be operated, therebyclosing a circuit from battery at RSI to the upper end of the winding ofrelay RS5. Relay RS5 does not operate, however, until the other end ofits winding is connected to ground through conductor 8 of cable |33 andsegment 5 of the distributor DR2, which occurs during the pulsing of theindicators. When brush b6 of distributor DRI reaches segment I4 of ringground from segment 4 of ring I2 is supplied over conductor 9, cables40| and |33, to energize the start magnet SM2 of distributor DR2, Fig.3. As previously described, the circuits set up by the first and seconddigit identification storage relays, the x relays and the range relayscoact to select gang relay GAI4, Fig. 3, and gang relay DGA00, Fig. 5.In this case the range code for the character 2 causes lead in cable 620to be energized to operate the range relay A (altitude) shown in Fig. 3.The pulses generated during the revolu tion of distributor DR2 andcontrolled by the circuits set up in the Data (Tens) and Data (Units)relays are now sent out over conductors I6 and of cable 305 to operatethe indicators AT and AU of row I4 in the record board and similarlyindicators AT and AU in row of the display board. This operation poststhe altitude 45 (4500 feet) in these indicator positions on both boards.

During the revolution of distributor DR2, a circuit was closed as thebrush b passed oversegment 5, from ground on ring 2 through the brushand segment 5, over conductor 8 of cable |33 to the lower end of thewindings of relays RS shown in Fig. 1. Since the upper end of thewinding of the RS5 relay shown in Group A previously had batteryconnected thereto upon the reception of the end-of-message signal, relayRS5 now operates and removes ground, at its armature and break contact|22, from conductor |2|. In the meantime the stepping ahead of theperforated tape through the tape transmitter TTR has opened the groundcircuit at contact of the auto-control switch AC because the slack tapeloop has been depleted. The removal of ground from conductor |24 as wellas from conductor |2| releases the relay L. Relay L upon releasing opensat its armature |29 and associated make contact the operating circuit ofrelay TC and the start magnet SMI of distributor DRI. Relay TC does notrelease immediately since it is locked up through its own contact 'l toground over conductor |4| supplied through armature 330 of the RELrelay, Fig. 3. When the distributor DR2 completes its revolution, relayREL is operated as previously described, and at its operated armature330 and break contact releases the relay TC.

The release of relay L removes the ground from the hunting circuit ofthe rotary switch magnet SSM, Fig. 1, so that unless another incomingmessage is waiting, the switch SS will remain at its previous position.

Operation of keyset Prior Vto the reception and posting of the incomingmessage hereinbefore referred to, the operator had operated the keysetshown in Fig. 2 in order to display in predetermined positions on therecord board and display board at least the identication numbersrelative to the various flights concerningl which information is to betransmitted, each flight being assigned to the particular section of thedisplay board containing the night data relating to a particular Fix. Onthe record board the locations may be chosen at random, but the Fix towhich the ilight is assigned is recorded cn a Fix storage indicator suchas F in horizontal row I4 in Fig. 6 or row 00 in Fig. "1. In initiallysetting up theserindicators it is not necessary for any data, such astime and altitude, to be inserted, although it is frequently done lnaccordance with proposed flight plans, and upon the reception ofincoming signals relating thereto the actual data is posted instead ofthe estimated data.

Since the rows 00 to I4 in the record board are assigned at random, eachrow is provided with a group of present position storage relays`designated PPT and PPU, Figs. 6 and 7, which have recorded upon them thehorizontal row number occupied by the same flight in the display board.Each horizontal row in the record board is also provided with a Fixindicator F, as above stated, upon which is stored the Fix in which theflight is displayed on the display board. Each horizontal row in therecord board is also providedv with two recording new position indicatorunits such as NPT and NPU, Figs. 3 and 4, which record the newhorizontal position in the display board to be occupied by the flightdata posted in that row of the record board.

Referring to the keyset of Fig. 2, it will be seen that there are sevenrows of push buttons which are of the mechanical locking type, asindicated by the slidable locking bar 200 which extends to all of thekeys SEQ to A in the row. When any key of the row is depressed, thetapered or coni.. cal edge of the body portion of the key shifts the barto the right, and passes through an aperture in the bar and the key isheld depressed by the bar until the key release magnet KR is energized,which moves the locking bar to the left and releases the key. Onelocking bar is provided for each row of keys, and each bar is releasedby magnet KR. The left hand row of seven push buttons is used to selectthe type of operation to be performed by the keyset. 'I'he next two rowsdesignated PP Tens and PP Units are used to set up present positions byoperating various combinations of the PPT and PPU relays, Figs. 6 and 7,in permutation code. The next two rows designated Data Tens and DataUnits are used to control the number of impulses sent to any of theindicator units selected by means of the range keys NP, F, I, T and A inthe left hand row. The last two rows, designated Hor. Pos, Tens(horizontal position tens) and Hor. Pos. Units (horizontal positionunits), are used to select the row in the record board where a flight isto be initially posted. Wheninformation regarding a proposed ight isreceived by the operator,

the iiight number is posted` in a selected row in the record board anddisplay board.

Prior to receiving the preceding message regarding ilight 34 over theline from teleprinter I III, Fig. 1, the local operator will have postedthe night number 34 and the Fix 1 on the record and display boards bythe use of the keyset. The operator will have also selected a row in thedisplay board where this flight may initially be displayed in vproperrelatio-n to other flights on the display board. The operation ofposting flight 34 Fix .1, in krow I4 of the record board and row of thedisplay board will now be described. Since the information to be postedcomprises the flight number 34, the present position 00, and the Fix 1,two keyset operations will be required. The first operation will be theposting of the flight number 34 in the Identification, Range and thestorage of the present position 00 in the PPT and PPU relays in theselected row I4 of the record board. The operator depresses the 0 keysin the PP Tens and PP units rows. Key 3 in the Data Tens row and key 4in the Data Units row are operated., and in order to select row I4 ofthe record board which happened to be idle at the time, the operatoralso depresses key I in the horizontal position tens row and key 4 inthe horizontal position units row.

The last operation is that of selecting the range, which is performed bydepressing the I key in the left hand row of the keyset. The left handcontacts of the I key close a circuit from ground at 20| through theclosed contacts of the key, and over conductor 202 to the winding of theK relay, Fig. 1, and thence to grounded battery. As previously describedfor the operation of the L relay, the' K relay applies ground throughits operated armature |26 and the upper armatures on relays L, RI and R2to all contacts of bank A of the selector switch SS except terminals 4and I which were disconnected at armature I2@ and associated breakcontact of relay K. The application of ground causes the selector switchmagnet SSM to be energized and step the switch through itsself-interrupting armature |28 until it comes to rest on either terminal4 or 8, whichever was reached first. The operation of relay K, alsocloses a path to operate relay KS. Fig. 2, from battery on armature |52cf relay K and associated make-contact, conductor |53, winding of theKS' relay, conductor 204, terminal 4 of bank C of switch SS, wiper of.bank C, conductor |54, terminal 4 of bank B of switch SS, wiper of bankB, conductor 4 in cable I33,

conductor 4 in cable 40|, Fig. 4, break contact and armature '|00 ofrelay. SST, Fig. 7, conductor I in cables 40| and I33,'segment I of ringI of distributor DB2, Fig. 3, and thence through brush l1 to thegrounded feeder ring 2 of the distributor. thereby operating relay KS,Fig. 2, and closing through the various groups of contacts v controlledby the armature 204 of that relay.

The closure of the contacts connected to the horizontal position tensand horizontal position units keys, selected and operated gang relay GAMover the path to be described. Ground through the contact of key I inhorizontal'position tens row operates a corresponding tens relay HPTIIJ,Fig. 2. Ground through the contacts of horizontal position units key 4applied ground to the No. l contacts on all l-IPT relays, but HPTIObeing the only relay operated, the final path is over lead I4 in cable298, conductor 6I4, Fig. 3,4 to the winding of gang relay GAIII andthence to grounded battery, operating GAI4. The operation of the KSrelay, Fig. 2, also closed a circuit from' ground 20| through thenormally closed contacts of the SEQ push button, over conductor 209 tothe winding of start magnet SM2 and thence to grounded battery,operating the start magnet and releasing the brush arm b of DRZ. Aspreviously described, the rst operation produced by the distributor isthe operation of relay M, Fig. 5, when the brush b passes over segment2. This ties togethervthe various multiples -I to '505 -of the displayboard. When the brush b connects ground to segment 3 of ring I of thedistributor, the path is completed over lead 334 through any operated PPtens or PP unit keys, Fig. 2, which in this case are the 0 keys in eachrow, over conductor 2I0, contact of KS relay, conductor IS in cable305contact of operated relay GAM, conductor I in cable 6I'I to the resetcoils R of -the APPT and PPU relays which are connected in series byconductor 650, and thence to grounded battery y|549. The operation ofthe reset coils R of these relays releasesv the'armatures ofthosewhichwere previously set.

The right hand vcontacts of the PP tens key 0, Fig. 2, have closedcircuits from ground at 2I2 to conductors 2H, 245 and 2I6 which continuethrough conductors 20, 2l and 23 of cable 305, and conductors 2, 3 and5-of cable 6I'I, to

the operate windings of relays PPTI, PPT2 and PPT4, Fig. 6. Thiscombination represents the permutation code for the digit 0. Similarly,the left hand contacts Yoi the PP units -key 0 closed circuitsiromground 2| 8 to conductors 220, 22| and 222, contacts of KS relay, vandconductors 24, 25 and 27 of vcable 305, contacts of relay GAM,conductors 6, l and 9 of ,cable BII, to the operating windings 0 ofvrelays PPI, PPU2 and PPU4, Fig. 6,` thereby registering .thepermutation code for. the digit-.0 in the PPU relays.

When the contacts ofthe PPT and PPU relays are closed, a circuit isclosed from ground at 336, Fig. 3, through contacts of the relay GAI 4,

-- over conductorsv 4 to II of cable 338 to the con- -tacts of the PPTandPPU relays, and thence through the contacts of the operated -ones ofthese. relays over conductors 1I, 2, 4, 5, Gland 8 of cable SIE tothewindings of relays PTI, PT2, and PT4, PUI, ,P1212 and PU4, Fig 7, tobattery.

The combination set up by the operated PTI, ,PTE and PT4 relays,`through the pyramidal larmature arrangement shown,energizes conductor 0which connects to the winding of the PT 00 relay.Y The operation of thisrelay completes a `circuit from the previously-energized 0 lead of thePU relay group .to lead 00 in `cable. 10|. This path completes ttheoperating circuit for relay DGA 0 0, 5. 'Ihe operationof relay DGA 00connects lthe group ofindicatorunits in the 00 row., of the displayboard to -the pulsing multiple.

The operation of the I -push button in the left hand row of keys showninvFig. 2 has closed a circuit from ground at 20| through the right handcontacts of the push button I, over conductor 3 of4 cable 225 to thewinding of the I range relay, Fig. 3. This relay connects the pulsingleads from the relays PI, P2,P4, and P'I to. the pulsing multipleconductors I 2 and I3 in cable 355 where they4 eventually terminate onthe coils of the IT and IU indicators inltherecord board horizontal rowI4, and the IT and -IU indicators in row 00 of the display board.

VAs the brush b of the distributor DR2 cony tinues its rotation,circuits closed through the .evennumbered segments 4 to 22,. inclusive,cause

